Automate rotating nodes after creating an etcd snapshot

[markusewalker]

Issue Description

Currently, the Go framework has basic support for snapshot restore for cluster provisioning. One test that does not exist is during a fresh install or an upgrade of a downstream cluster, we do not rotate nodes. When performing etcd snapshot and restores, it shouldn't be assumed that a user will never not rotate nodes.

For that, we should automate rotating nodes after a snapshot has been created, for fresh install and upgrade usecases.

[markusewalker]

Update: I have a local fix for this. I'm waiting to open a PR after the shepherd repo is finalized and there are no conflicts.